Conventional energetic materials, which are used as fill material in ordinances, are typically sensitive to shock or impact. As such, an ordnance is sometimes unintentionally detonated by impact with bullets, fragments, or shaped charge jets (“SCJ”), causing injury or death to personnel or damage to life, equipment, facilities, or infrastructure. Moreover, unintentional detonation often occurs during storage, handling, or transportation of the ordnance. To avoid these problems, insensitive munitions (“IM”) are being researched and developed. An IM should minimize the probability of being inadvertently initiated and should provide reduced severity of collateral damage to facilities and personnel when subjected to unintentional stimuli.
A trinitrotoluene (“TNT”)-based explosive is commonly used as a high explosive fill in bombs, artillery rounds, and various munitions. Energetic solids, such as cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX,” also known as hexogen or cyclonite), cyclotetramethylene tetranitramine (“HMX,” also known as octogen), or aluminum, have been used with TNT to modify its performance properties. Composition B (“Comp B”) is a TNT-based explosive and is one of the most commonly used explosives in the world because it has good performance characteristics and is relatively inexpensive to produce. Comp B includes TNT (39.5% by weight (“wt %”)), RDX (59.5 wt %), and wax (1.0 wt %). However, Comp B often reacts violently when unintentionally exposed to stimuli. High performance replacements for Comp B have been developed that have reduced hazard sensitivity and are produced using low cost and commercially available ingredients, preferably non-toxic or non-carcinogenic. One such replacement is Picatinny Arsenal Explosive 21 (“PAX-21”), which includes 34.0% by weight (“wt %”) dinitroanisole (“DNAN”), 30 wt % ammonium perchlorate (“AP”), 35.75 wt % RDX, and 0.25 wt % n-methyl-4-nitroaniline (“MNA”). Other replacements are PAX-25, which includes 59.75 wt % DNAN, 0.25 wt % MNA, 20 wt % AP, and 20.0 wt % RDX, and PAX-28 which includes 39.75 wt % DNAN, 0.25 wt % MNA, 20 wt % AP, 20 wt % RDX, and 20 wt % aluminum.
“Phenomenal Aspects of Blast Output from the Heterogenous Detonation of Energetic Compositions” Tulis et al., p. 40-1 through 40-13, (1995), discloses a heterogeneous energetic composition that includes a fuel, an oxidizer, and lactose or starch. For instance, the energetic composition includes RDX, aluminum, ammonium perchlorate, and lactose.
“Shock-Dispersed-Fuel Charges-Combustion in Chambers and Tunnels,” Neuwald et al., 34th International ICT-Conference, Karlsruhe (2003) discloses an explosive composition that includes pentaerythritol tetranitrate (“PETN”), TNT, aluminum, and a hydrocarbon powder, such as polyethylene, sucrose, carbon fibers, or mixtures thereof. The hydrocarbon powder is packed around a core of the PETN.
U.S. Pat. No. 4,231,822 to Roth discloses an organic explosive material desensitized with an organic reductant, such as glucose. U.S. Pat. No. 4,248,644 to Healy discloses an emulsion of a melt explosive composition that includes a fuel, ammonium nitrate, an emulsifying agent, and a compound that forms a melt with the ammonium nitrate upon heating. The latter compound is a carbohydrate, such as a sugar, starch, or dextrin. The ammonium nitrate provides a discontinuous phase and the fuel provides a continuous phase. U.S. Pat. No. 4,507,161 to Sujansky et al. discloses a nitrate ester explosive composition that includes a solid additive. The solid additive is an oxidizing salt, a filler, or a carbonaceous material, such as a sugar. The explosive composition is a melt-in-oil type explosive composition and includes a continuous phase and a discontinuous phase. U.S. Pat. No. 4,722,757 to Cooper et al. discloses a melt-in-fuel explosive composition. A continuous phase of the explosive composition includes a water immiscible fuel and an emulsifier and a discontinuous phase of the explosive composition includes an oxidizer salt. The continuous phase and the discontinuous phase are substantially immiscible.
It would be desirable to prevent unintentional detonation of an ordnance by providing an explosive composition that is relatively insensitive to external stimuli, such as impact, without substantially affecting the energetic performance of the explosive composition.